The present invention generally pertains to a method and apparatus for implementing engineering change orders (ECOs).
Engineering change orders (ECOs) are very common for a design in progress owning to a multitude of factors that include but are not limited to improving performance (timing based), enhancing functionality and/or fixing existing errors. The need for an ECO is typically based off the results of design analysis, static timing analysis, etc.
Changes to the design are implemented via file-based methodologies. The tool being disclosed (lsiecoread) handles a file-based ECO, i.e., reads an input file that describes the changes that need to be made to the design and updates the layout database (Synopsys Apollo) representation of the design, accordingly. The tool being disclosed pertains to the field of application specific integrated circuit (ASIC) design, especially the physical design aspect wherein changes/modifications are made to the design database to allow for an accurate representation of the customer net list or design specification, both for meeting timing requirements and functionality.
Traditional file-based ECOs necessitate the user to write out the ECOs in a tool specific syntax that is non-trivial, non-comprehendible, error-prone and extremely time consuming.
Existing approaches include the creation of tool-specific ECO files (such as Avant! ECO files in the design flow of LSI Logic, Assignee of the present application) that have inherent disadvantages as described above. One primary drawback of the Avant! ECO files is that they are extremely difficult to read and comprehend, thus affecting designer productivity. The non-friendly syntax also makes the files extremely hard to edit and maintain.
Tool specific ECOs (Synopsys/Apollo ECOs) exist today that could be used. However, significant limitations and drawbacks of this approach include, but are not limited to: 1) ECOs have to be primarily net based; 2) inefficient from a creation/editing/maintainability standpoint; and 3) impacts designer productivity negatively.
Therefore, an improved method and apparatus for implementing ECOs is needed. The present invention provides such an improved method and apparatus for implementing ECOs. Features and advantages of the present invention will become apparent upon a reading of the attached specification, in combination with a study of the drawings.